Enthuware

I think the response is not fully correct, some options are though correct. example Option1 is correct, you can declare a sealed class without permits if classes which extend it are in the same java file as the sealed class

You are right. This has now been fixed and an explanation has been added..
thank you for your feedback!

I think we could apply the same assumption to Option 2. Meaning that it could be a valid sealed class declaration too if a subclass were defined in the same Java file.

I guess the question "Identity potentially valid declarations of sealed classes", especially the word "potentially" can lead to different interpretations.

Thanks.

Very true indeed!
Updated again.

I cannot assume option 2,

"public sealed class DocType { }"

as a valid option.

Permits clause is required. Otherwise, it does not compile.

Please, fix it. Thank you.

permits is not required if the permitted class is in the same file.